Among civil litigators, 2015 was the “year of the expert,” with multiple decisions from the appellate courts on various issues related to expert evidence. Over the last two years, lower courts have been applying the principles articulated in 2015 so that we can now look back on how the seminal decisions have affected litigation practices.

I would first like to look at how trial courts and tribunals are applying the rules surrounding production of an expert’s working file, as opined in Moore v. Getahun 2015 ONCA 55.


The Moore v. Getahun decision in 2015 clarified when an expert’s working file will be produced. The starting point is that “the file,” i.e.: non-foundational documents that contain communications between the expert and counsel, is subject to litigation privilege. However, litigation privilege is not absolute. Where an opposing party can show “reasonable grounds to suspect that counsel communicated with the expert in a manner likely to interfere with the expert’s duties of independence and objectivity,” a court can order production of draft reports and notes of consultations between counsel and the expert.

To date, there have not been any reported decisions where a court overturned the presumption and ordered production of the expert’s file. Instead, the decisions reiterate the high threshold required for disclosure and have repeatedly held that a mere allegation of bias is an insufficient.

In C.S. v. R.S. 2017 ONCJ 156, the defendant sought production of the file on the basis that a letter showed that counsel had directed the narrow parameters of the expert’s report. The judge disagreed that the letter satisfied the high threshold for disclosure. The judge found that counsel’s direction was given to assist the expert in providing relevant information, not exert “improper influence.” The judge said that the expert “gives no indication that she has been told to limit the information to specific facts, dates, concerns, etc.” The judge went on to deny the defendant’s motion for production, “[the defendant] cannot be found to have met the threshold of establishing a reasonable suspicion that improper influence has occurred by counsel.”

In Law Society of Upper Canada v. Kivisto, the defendant moved for production of communications between counsel and two expert witnesses who were called to testify on disbarrment procedures in other jurisdictions. The defendant claimed that disclosure was warranted because there was evidence of a discussion regarding his complaints about the experts. He argued this suggested that the experts may have fabricated evidence to rebut these complaints.

The tribunal viewed this as a mere “hypothesis” falling below the threshold for production, “in our opinion, this falls short of what the Court of Appeal in Moore … said was required to compel production of privileged documents. As such, there is no factual foundation to support a reasonable suspicion that the Law Society is acting improperly such that privilege should not be maintained.”


Of special note are two very recent decisions regarding production of counsel’s instructing letter to the expert. In Maxrelco Immeubles Inc. v. Jim Pattison Industries Ltd. 2017 ONSC 5836, the court concluded that, absent a foundation to support a suspicion of improper influence, there was no obligation to produce the instructing letter. The court further concluded that rule 53.03(2.1)3 was satisfied when the information required by that rule was set out in the expert report itself. This decision was followed in Scaffidi-Argentina v. Tega Homes Developments Inc. 2017 ONSC 6530.

These decisions are contrary to the earlier decision of a master in Nikolakakos v. Hoque 2015 ONSC 4738. In the earlier case, it was held that letters of instruction are foundational information that must be disclosed but that this obligation of disclosure only arises once the party who retained the expert has exercised their option of whether to call the expert as a witness at trial.


Recent decisions show that the threshold for the disclosure of communications between counsel and expert remains high. A party who seeks such disclosure must demonstrate a factual foundation for improper interference with an expert’s independence and objectivity; disclosure will not be granted so that a mere hypothesis can be explored or confirmed.

Furthermore, moving parties must keep in mind that certain communications between counsel and an expert are not only proper but encouraged, particularly where the purpose is to assist the expert in providing a relevant opinion that will be useful to the court.

Lastly, the most recent decisions on the issue indicate that, so long as the requirements of rule 53.03 are met within the expert’s report itself, disclosure of counsel’s instructing letter is not required.

The next article in this series will address the issue of expert “ghost writing.”

This article originally appeared on The Lawyer's Daily website published by LexisNexis Canada Inc.